From David Ould at StandFirm:
So Joshua burned Ai and made it forever a heap of ruins, as it is to this day. And he hanged the king of Ai on a tree until evening. And at sunset Joshua commanded, and they took his body down from the tree and threw it at the entrance of the gate of the city and raised over it a great heap of stones, which stands there to this day.
The King of Ai, as leader and representative of his people, bears the full punishment of God due to all who oppose Him. The name “Ai” means “ruins” and their king’s body remains under a ruin of stones, a permanent testimony to the everlasting ruin that falls upon anyone who would stand against God and His people.
Centuries later there would be another King. He too would die on behalf of His people, die because He stood for them in their terrible guilt in not acknowledging the lordship of the one true God. He too would be hung on a tree (Gal 3:13). His dead body would be taken down at sunset (Matt. 27:57-59). His body would be hidden away behind rock (Matt. 27:60).
But this One would not stay there forever. On the third day He was raised from death.
The king of Ai lies in eternal ruins as a symbol for all who follow after him. The King of Life’s body was rebuilt, better than ever (John 2:19) and those who belong to Him reign with Him for eternity (Rev. 20:6).
El Elyon, God Most High,
We extol Your greatness in the Mississippi Delta. Amen.